STUDIES ON THE PERSISTENCE OF MALARIAL ANTIBODY RESPONSE

Abstract

Collins, William E (P.O. Box 80190, Chamblee, Ga. 30005), J. C Skinner and G. M. Jeffery. Studies on the persistence of malarial antibody response. Amer. J. Epid., 1968, 87: 592–598.—Sera from 95 patients having had induced infections with P. falciparum, P. malariae, P. vivox or P. ovale were tested for presence of specific antibody using the indirect fluorescent antibody method. The intervals between termination of the infections and acquisition of the sera ranged from approximately 6 months to 26 years. Specific serum dilution end-points high enough to be considered positive (1: 20 or greater) were found as late as 8 years after termination of a P. faldparum infection and 13 years after termination of P. malariae. For P. vivax, positive responses could not be found three years after termination of the infection. Where patients had experienced multiple infections with malaria, positive responses were seen after even longer periods subsequent to termination of the infections. In general, for all sera tested, the median response decreased sharply when three years had elapsed after termination of the infections and continued to decrease with time thereafter. With patients who had experienced P. malariae infections which had not been terminated by curative antimalarial treatment, sera collected 15 to 24 years after the last known patent parasitemia frequently yielded a positive FA response.